Alberto Moreno looks unlikely to feature for Liverpool this weekend in their all-Premier League FA Cup fourth-round meeting with West Bromwich Albion, but has vowed to battle hard to recover his starting left-back berth from Andrew Robertson after returning to first-team training.

Moreno had surprisingly established himself as manager Jurgen Klopp's first-choice option at the position despite a disappointing 2016-17 campaign in which he was consistently overlooked in favour of midfielder James Milner and the £8m ($11.4m) summer arrival of the highly-regarded Robertson from relegated Hull City.

The Spaniard made 20 appearances across all competitions before missing each of the last 10 matches with an ankle injury that saw him limp out of the first half of the 7-0 Champions League demolition of Spartak Moscow on 6 December.

Though Moreno is now back training with the rest of his teammates at Melwood and insists the issue is "getting better each day", he concedes he can feel the ankle is still "not quite right" and that he is "waiting for this little discomfort to go away" before easing himself back into contention.

Quizzed regarding a potential return date, Moreno appeared to preach caution and cast doubt on the possibility of him being thrust back into the picture at Anfield on Saturday night (27 January).

"I honestly don't know," he told Liverpool's official website. "It'll be the manager who decides exactly when I come back but what I do want to make sure of is that I'm fully 100 per cent when I do make my comeback. You don't want to not live up to what you can do when you're fully fit, so it's a case of getting that match fitness at 100 per cent so as not to let people down."

Robertson - described as "very important" by Klopp - has thrived in Moreno's absence following a frustrating beginning to life on Merseyside, starting all but one of those last 10 matches and earning plenty of plaudits for his consistent performances.

Moreno is all too aware that he has a fight on his hands to wrestle back that starting gig from the Scottish international, who he admits has fully grasped his opportunity.

"You've got to be absolutely honest and sincere and say that he's doing really, really well," Moreno said. "He's put in some great performances and played some great matches. It was tough for him at the start of the season, not being involved, I'm sure. It's also never easy to come into the first team mid-season, so I think he's coped with that really well."

He added: "It's always tough to get your place in the first team at Liverpool Football Club. Obviously, as a result of my injury, [Robertson] has taken his chance and grabbed it with both hands. But I'm training really hard now and determined to do all that I possibly can through hard work to try and win my place back."

Alberto Moreno
Alberto Moreno has missed each of Liverpool's last 10 matches with an ankle injury suffered against Spartak Moscow Dan Istitene/Getty Images